Printing group of an offset rotary printing machine

ABSTRACT

A printing group of an offset rotary printing machine includes at least one forme cylinder, one transfer cylinder and at least one inking system. Two of these printing groups are arranged opposite to each other. The arrangement of the printing group in relation to each other can be arranged in an axial direction which is parallel to the axes of rotation of the cylinders.

FIELD OF THE INVENTION

The present invention is directed to a printing group of an offsetrotary printing press. Several printing groups are cooperativelyarranged and at least one is shiftable in a direction parallel to theaxes of rotation of the cylinders.

BACKGROUND OF THE INVENTION

A print unit for a multi-color web-fed rotary printing press for sheetwork is known from EP 0 749 369 B1. Two printing groups are arranged ina so-called bridge construction opposite each other in a frame. Thearrangement of the printing groups relative to each other can be changedtransversely to the direction of the axes of rotation of the cylinders.

An offset printing press is known from DE 198 33 468 A1. This has twooppositely located print units which can be arranged, separated along avertical plane of separation, and their distance from each other can bechanged.

A web-fed rotary printing press is described in EP 0 958 917 A1, andwhich has several printing units, each consisting of two printinggroups. In this case, the printing groups are arranged on top of eachother and can be separated along a substantially horizontally extendingplane of separation. The individual printing groups can be displacedvertically transversely in respect to the axes of rotation of thecylinders, so that a distance can be provided between the individualprinting groups, for example for maintenance work.

A web-fed rotary printing press is known from EP 0 638 419 B1, whoseindividual components, in particular the cylinder elements and theirassociated ink and dampening units, are seated in a support frame. Inthis case, the ink and dampening units are embodied as displaceableunits, which can be pulled out of the printing group in an axis-paralleldirection of the axes of rotation.

DE 199 19 864 C1 discloses two five-cylinder print units, which can bedisplaced relative to each other either transversely to or along theaxis of rotation of the cylinders.

SUMMARY OF THE INVENTION

The object of the present invention is based on providing a printingunit for an offset rotary printing press.

In accordance with the present invention, this object is attained byproviding printing groups that are arranged oppositely to each other. Aspacing distance between the opposing groups, in a direction transverseto the axes of rotation of the cylinders can be changed. The arrangementof the printing groups in relation to each other can be changed in adirection approximately parallel to the axes of rotation of thecylinders. The opposing printing groups can be arranged as bridge unitsin a so-called bridge construction.

The advantages to be gained by the present invention primarily lie inthat the required space in front of and behind each of the printinggroups, which are respectively arranged in pairs, can be reduced. Forperforming maintenance work, it is not required to move the printinggroups away from each other transversely in relation to the axes ofrotation of the cylinder, as taught in the prior art. Instead, theprinting groups are arranged to be laterally offset in an axis-paralleldirection of the axes of rotation of the cylinders. The printing groupsthus become accessible for any required work without the distancebetween the printing groups transversely to the direction of the axes ofrotation of the cylinders needing to be changed. This measure isadvantageous, especially in those cases where several printing groups,which are arranged in pairs, are arranged one behind the other, forexample in the form of printing towers arranged one behind the other. Inthis case, it is possible to place the pairs of printing groups, whichare arranged one behind the other, at reduced distances from each other.A further advantage ensues from the fact that certain parts of theprinting groups, namely the parts which are located the farthest towardthe outside on a side of a printing group, are fully accessible withonly a relatively small lateral offset between the printing groups.Because of this, it becomes possible, for example, to arrange parts ofthe printing groups which are particularly maintenance-intensive in thisarea of the printing groups. For inspection or maintenance of thesemaintenance-intensive parts of the printing groups, it is not necessaryto move them completely apart from each other, but only far enough sothat the parts to be maintained are sufficiently accessible.

Not only individual components, consisting of ink and dampening units,can be pulled laterally out of the printing groups of the presentinvention. Instead, the entire oppositely-located printing groups can bearranged laterally offset. It is thus possible, in particular, toperform maintenance work on substantially all parts of the printinggroups without further steps for opening the printing groups becomingsubstantially necessary.

It is basically sufficient if, for separating the printing groups whichare located opposite each other, that these printing groups can bearranged laterally offset in relation to each other in an axis-paralleldirection of the axes of rotation of the cylinders. However, it isparticularly advantageous if, in addition, the printing groups can bearranged so that their distance in relation to each other, transverse totheir axes of rotation, can be at least slightly changed. In the courseof moving a printing unit consisting of two oppositely-located printinggroups apart, it is then possible, for example, to first displace theone printing group in a direction transversely to the axes of rotationof the cylinders until at least a slight distance between the printinggroups has been created. By this movement transversely to the directionof the axes of rotation of the cylinders, it is possible to bring theprinting groups initially out of engagement with each other. It isthereafter possible to displace the printing group in an axis-paralleldirection to the axes of rotation of the cylinders in order to make theparts located in the interior of the printing group accessible.

Advantageous embodiments ensue from the combination of characteristicsof the invention with characteristics already known from the prior art.Characteristics, whose combination into an arrangement of printinggroups in accordance with the invention is particularly advantageous,are known from EP 0 749 369 B1 and DE 198 33 468 A1.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the present invention are represented in thedrawings and will be described in greater detail in what follows.

Shown are in:

FIG. 1, a side elevation view of a first embodiment of printing groupsin accordance with the present invention,

FIG. 2, a top plan view of a schematic representation of the arrangementof printing groups in accordance with FIG. 1 in the operational state,

FIG. 3, a top plan view of a schematic representation of the arrangementof printing groups in accordance with FIG. 1 when the print groups areseparated in a direction transverse to the axes of rotation of thecylinders,

FIG. 4, a top plan view of a schematic representation of the arrangementof printing groups in accordance with FIG. 1 when the print groups areopened in a direction parallel to their axes of rotation,

FIG. 5, a side elevation view of a second embodiment of printing groupsin accordance with the present invention,

FIG. 6, a top plan view of a schematic representation of the arrangementof printing groups in accordance with FIG. 5 in the operational state,and in

FIG. 7, a top plan view of a schematic representation of the arrangementof printing groups in accordance with FIG. 5 in the opened state.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

An offset rotary printing press, or a section of an offset rotaryprinting press, has, for example, eight printing groups in a modularconstruction of printing units, of which only the printing groups 01, 02which make up one printing unit are represented in FIG. 1. Theconstruction of each of the individual printing groups 01, 02corresponds, in the essential characteristics of the component of eachgroup, to the construction described in DE 198 33 468 A1.

Each one of these printing groups 01, 02, as seen in FIG. 1, is embodiedas a so-called 5-cylinder printing group, and each printing group 01, 02has substantially two forme cylinders 03, 04, 06, 07, for example platecylinders, two transfer cylinders 08, 09, 11, 12, for example rubberblanket cylinders, and one counter-pressure cylinder 13, 14, for examplea satellite cylinder. The journals of these cylinders 03, 04, 06, 07,08, 09, 11, 12, 13, 14 are seated in respective lateral frames 16, 17 oneach side of the offset rotary printing press. In the first preferredembodiment, the journals of the transfer cylinders 08, 09, 11, 12 arepivotably seated in eccentric bushings or in accordance with three-ringbearing technology, so that the transfer cylinders 08, 09, 11, 12 can beplaced against and away from the associated counter-pressure cylinders13, 14. It is also possible to place the counter-pressure cylinders 13,14 against the associated transfer cylinders 08, 09, 11, 12, for exampleby use of eccentric bushings, three-ring bearings or by linear guidance.

In the first preferred embodiment, each cylinder 03, 04, 06, 07, 08, 09,11, 12, 13, 14 is provided with its own, rpm-controlled and/orposition-controlled drive motor. However, it is also possible to assigna drive motor to each pair of forme and transfer cylinders 03, 08; 04,09; 06, 11; and 07, 12, and to positively couple each pair. In thiscase, each counter-pressure cylinder 13, 14 also has its own drivemotor, or it can be coupled to one of the pairs of forme or transfercylinders 03, 08; 04, 09; 06, 11; or 07, 12. It is also possible toassign only one drive motor to each printing group 01, 02 and totransmit the drive moment to be transferred by means of a verticalshaft, for example. Independently of the type of drive mechanism it ispossible to arrange a coupling between one or several cylinders and eachof the associated drive mechanisms, so that each individual cylinder orcylinder group can be separately switched in. In any case, the drivemotors for each printing group are fixedly assigned to each lateralframe 16, 17, associated with that printing group, independently of theposition and installation location of the printing groups 01, 02, sothat in the printing group 02, which is placed pivoted by 180° around avertical line, the drive motors are arranged on the opposite side of theprinting press when compared with the drive motors associated with theprinting group 01. One ink unit 18, 19, 21, 22, and one dampening unit23, 24, 26, 27 is assigned to each one of the forme cylinders 03, 04,06, 07. In the first preferred embodiment represented in FIG. 1, theprinting group 01 is embodied as a V-printing group 01, for example, andthe printing group 02 as a W-printing group 02, for example. Theprinting groups 01, 02 can each be operated independently of each otheras five-cylinder printing groups located opposite each other, so that ina first mode of operation, which is not specifically depicted, twooppositely located printing groups 01, 02 functionally constitute aten-cylinder satellite printing group. During this first operatingstate, the transfer cylinders 08, 09, and 11, 12 interact with thecounter-pressure cylinder 13 of the V-printing group 01 and with thecounter-pressure cylinder 14 of the W-printing group 02, respectively.In a second operating state, two five-cylinder printing groupsfunctionally act as a nine-cylinder satellite printing group. Thissecond operating state is represented in FIG. 1. For this purpose, thetransfer cylinders 08, 09, 11, 12 of the V-printing group 01 and of theW-printing group 02 can be placed against and away from thecounter-pressure cylinder 13 of the V-printing group 01. In this secondoperating state, the counter-pressure cylinder 14 of the W-printinggroup 02 is not part of the printing process.

The printing groups 01, 02 are fastened in a support element, of whichonly the upper and lower transverse supports 28, 29, respectively havebeen schematically represented in FIG. 1. In this case, the V-printinggroup 01 is connected, fixed in place, with the transverse supports 28,29, while the W-printing group 02 is displaceably seated in the supportelement. The printing unit or section of the offset rotary printingpress formed from the printing group 01, 02 can be opened by the pressoperators, in particular for servicing and maintenance. The requiredactuating movements for opening the printing unit or section formed fromthe printing group 01, 02 are schematically depicted in FIGS. 2 to 4.

In FIGS. 2 to 4, the printing groups 01, 02 have only been schematicallyrepresented, with the surrounding support elements left out. In FIG. 2,the printing groups 01, 02 are represented in a top plan view in theoperating state shown corresponding to the operating state in FIG. 1.The movably seated printing group 02 is locked together with the fixedlyseated printing group 01, so that the printing groups 01, 02 togetherconstitute a fixed-in-place printing unit or section of the offsetrotary printing press. For opening the printing unit or section, theprinting groups 01, 02 are first transversely separated, as representedin FIG. 3, in that the printing group 02 is displaced during anactuating movement indicated by the movement arrow 28 in a directiontransversely to the axes of rotation of the cylinders 03, 04, 06, 07,08, 09, 11, 12, 13, 14. A transverse separation distance between theprinting groups 01, 02 is created by this, so that the printing groups01, 02 are no longer in engagement with each other. Subsequently, theprinting group 02 is displaced axially or laterally toward the sideduring an actuating movement, as indicated by the movement arrow 32 in adirection axis-parallel with the axes of rotation of the cylinders 03,04, 06, 07, 08, 09, 11, 12, 13, 14, as represented in FIG. 04, so that,depending on the lateral offset between the printing groups 01, 02,increasingly larger areas of the interior of the printing groups 01, 02become accessible for servicing and maintenance work. In the process,the printing group 02 can be displaced outward, i.e. in the preferredembodiment represented toward the side, to such an extent, that theprinting groups 01, 02 are no longer located opposite each other, sothat all areas of the interior of the printing groups 01, 02 areaccessible from work platforms arranged in the areas 33, 34. For closingthe printing unit or section of the offset rotary printing press that isconstituted by the printing groups 01, 02, the printing group 02 isdisplaced in a reversed sequence and is finally locked to the printinggroup 01.

FIG. 5 shows a second preferred embodiment of an arrangement of printinggroups 48, 49, 51, 52,58, 59, 61, 62 in accordance with the presentinvention. The upper supports 40, 41, as well as the lower supports 42,44 of a multi-color web-fed rotary printing press receive these severalprinting groups 48, 49, 51, 52,58, 59, 61, 62, which are fixed on thesupports and which are arranged on top of each other, in a left frameelement 55 and in a right frame element 65 formed on the lateral frames46, 47. The printing groups 48, 49, 51, 52 seated in the left frameelement 55 are seated fixed in place and will be called the left, fixedprinting group 48, 49, 51, 52 in what follows. Furthermore, a rightframe element 65, which is displaceable on rollers 53, 54 and is formedby the right lateral frames 56, 57, is arranged between the uppersupports 40, 41, and the lower supports 42, 44. The right, movableprinting groups 58, 59, 61, 62 are arranged opposite the left, fixedprinting groups 48, 49, 51, 52 in the movable lateral frames 56, 57 ofthe right frame element 65.

In their essential printing characteristics, the construction of theindividual printing groups 48, 49, 51, 52 and 58, 59, 61, 62, and of theprinting units or sections formed thereof corresponds to theconstruction described in EP 0 749 369 B1. Each printing group 48, 49,51, 52 and 58, 59, 61, 62 respectively consists of a transfer cylinder63, for example a rubber blanket cylinder, which interacts with a formecylinder 64, for example a plate cylinder. The forme cylinder 64 isprovided with a dampening agent by a dampening unit 66 and with ink byan ink unit 67. The ink unit 67 can, for example, consist of an inktrough with an ink roller, wherein the ink roller transfers its printingink to the forme cylinder 64 by operation of intermediate inkapplication rollers. In place of two ink application rollers, it is alsopossible to use only one smaller or larger ink application roller. It isalso possible, for example, to use a chamber doctor blade in connectionwith a screen roller, or anilox roller, for example, in place of an inktrough, as well as an ink application roller. However, a conventionalink unit can also be employed.

Each dampening unit 66 can be embodied as a spray dampening unitconsisting of a known spray device, for example a strip with spraynozzles, whose sprays are directed on a dampening agent applicationroller. This dampening agent application roller is connected with theforme cylinder 64.

The printing groups 48, 49, 51, 52, fixedly arranged on the left lateralframes 46, 47 of the left frame element 56 between the supports 40, 41;42, 44 as well as the printing groups 58, 59, 61, 62, arranged on top ofeach other between the supports 40 41; 42, 44 in the displaceable rightframe element 65, are each arranged with their transfer cylinders 63facing each other, so that a web 68 or 69 can be imprinted on bothsides. As a result, the printing group 48 together with group 58, theprinting group 49 together with group 59, the printing group 51 togetherwith group 61, and the printing group 52 together with group 62 eachcomprise a bridge printing unit, or a print unit in bridge construction.

In this case, the right printing groups 58, 59, 61, 62 are arranged inthe displaceable right frame element 65 in such a way that they can bedisplaced relative to the left printing groups 48, 49, 51, 52horizontally in an axis-parallel direction of the axes of rotation ofthe cylinders 63, 64. To make this function clear, the left and theright frame elements 55, 65 are represented in FIGS. 6 and 7 in a topplan view. The representations in FIGS. 6 and 7 are purely schematic,with all details not required for understanding the function having beenleft off. The left and the right frame elements 55, 65 are representedin the operating state in FIG. 6, in which they are locked together.Following unlocking, the right frame element 65 can be laterallydisplaced in an axis-parallel direction in respect to the axes ofrotation of the cylinders 63, 64, as indicated by the lateral movementarrow 71. Rails 72, 73 are provided for this purpose between thesupports 40, 41, 42, 44, on which rollers 53, 54 are seated.

In addition, the right printing groups 58, 59, 61, 62, which aresupported by the right frame element, can be displaced relative to theprinting groups 48, 49, 51, 52 in the direction of the axes of rotationof the cylinders 63, 64.

As represented in FIG. 7, the right frame element 65 can be displacedlaterally to the side, i.e. in the embodiment represented toward theright, until the right and left printing groups 48, 49, 51, 52 and 58,59, 61, 62, respectively are completely separated from each other, andtherefore are easily accessible to the press operators for service ormaintenance work from the work platforms arranged in the areas 74 or 76.For example, the displaceable right frame element 65 can be actuated bythe use of two reciprocally acting work cylinders, for example hydrauliccylinders. However, other types of driving are of course alsoconceivable, for example by electric motors. For example, guide stripsknown from EP 0 749 369 B1, can be used for guiding the right frameelement 65. For achieving a high degree of exact fit in the operatingposition of the displaceable right frame element 65, it is possible toprovide several pins, which can extend past the closing edge, on theframe element 65, and which can be brought into engagement withcorrespondingly arranged blind bores on the fixed-in-place left frameelement 55.

In the operating position depicted in FIG. 5, the displaceable frameelement 65 is secured against inadvertent displacement by a mechanicallyoperating locking element 77. The locking element 77 consists of athreaded bushing, seated fixed in place on the frame element 65, which,in the course of closing, forms a positive connection with a threadedspindle, seated fixed in place on the frame element 55. In the course ofthis locking connection, the threaded spindle is moved in the directionof the left frame 55 by a motor-driven threaded bushing.

During a stoppage of the printing press, it is possible for theoperators to manually change the printing plates on the forme cylinders64 of the left and right printing groups 48, 49, 51, 52 or 58, 59, 61,62. For this purpose the frame elements 55, 65 must be moved far enoughapart, so that the appropriate forme cylinders 64 are sufficientlyaccessible. Alternatively, it is also possible to change the printingplates on the forme cylinders 64 by use of a printing plate changingdevice 78, which is assigned to each printing group 48, 49, 51, 52 or58, 59, 61, 62. For example, the printing plate changing device 78 canbe embodied in the same way as the printing plate changing devicedescribed in EP 0 749 369 B1.

The driving of the individual printing groups 48, 49, 51, 52 or 58, 59,61, 62 can be provided by use of a vertical shaft, or by use ofindividual drive motors assigned to the individual cylinders. A suitabledrive concept is described in EP 0 749 369 B1, for example.

While preferred embodiments of a printing group in accordance with thepresent invention have been set forth fully and completely hereinabove,it will be apparent to one of skill in the art that various changes infor example the overall size of the printing press, the specific type ofweb being printed, and the like could be made without departing from thetrue spirit and scope of the present invention which is accordingly tobe limited only by the appended claims.

1. A printing unit of an offset rotary printing press comprising: afirst printing group in the printing unit and having a plurality offirst printing group components including at least a first framecylinder, a first transfer cylinder and a first ink unit, said firstprinting group components having first printing group component axes ofrotation extending in a first direction; a first printing group framesupporting said first printing group in the printing unit; a secondprinting group in the printing unit and having a plurality of secondprinting group components including at least a second forme cylinder, asecond transfer cylinder and a second ink unit, said second printinggroup components having second printing group component axes of rotationextending in a second direction parallel to said first direction; asecond printing group frame supporting said second printing group in theprinting unit; means supporting at least said first printing group, insaid first printing group frame, and said second printing group, in saidsecond printing group frame, for cooperation with each other to act witheach other as at least a first printing group pair, said at least afirst printing group pair being part of the printing unit which isconfigured as a bridge printing unit in bridge construction, said firstand second transfer cylinders of said first and second printing groupsbeing oriented toward each other and cooperating to print a web passingbetween said first and second transfer cylinders while said first andsecond printing groups are cooperating with each other to form saidbridge printing unit; and a support element supporting said at leastfirst printing group frame and said second printing group frame of saidbridge unit in the printing unit for movement of at least one of saidfirst printing group frame and said second printing group frame in theprinting unit with respect to the other one of said at least firstprinting group frame and said second printing group frame in said bridgeunit in the printing unit formed by the cooperation of said firstprinting group and said second printing group in a direction parallel tosaid first and second printing group axes of rotation of said cylindersto separate said first and said second printing groups, which cooperateto form the printing unit, laterally with respect to each other in saiddirection parallel to said first and second printing group axes ofrotation to separate said printing groups of the printing unit apartfrom each other to provide access to said components of both of saidfirst and second printing groups in response to said lateral movement ofsaid one of said first printing group frame and said second printinggroup frame in the printing unit.
 2. The printing unit of claim 1further wherein said at least first and second printing groups aresupported so that a distance between said first and second printinggroups in a direction transverse to said first and second printing groupaxes of rotation can be changed.
 3. The printing unit of claim 1 whereinone of said first and second printing groups is fixed.
 4. The printingunit of claim 1 wherein said first and second printing group frames canbe locked together in a operational state of the printing press.
 5. Theprinting unit of claim 1 further including at least a second printinggroup pair, said second printing group pair being arranged on top ofsaid first printing group pair.
 6. The printing unit of claim 1 whereinsaid support element includes transverse supports and vertical supports.7. The printing unit of claim 1 wherein said first and second printinggroup frames are separable horizontally.
 8. The printing unit of claim 7wherein one of said first and second printing group frames is fixed andthe other of said first and second printing group frames is displaceablerelative to said one.
 9. The printing unit of claim 8 further includingrollers supporting said displaceable one of said first and secondprinting group frames.
 10. The printing unit of claim 1 furtherincluding a third forme cylinder, a third transfer cylinder and a firstcounter-pressure cylinder in said first printing group and a fourthforme cylinder, a fourth transfer cylinder and a second counter-pressurecylinder in said second printing group.
 11. The printing unit of claim10 wherein said first printing group and said second printing group area v-printing group and a w-printing group.
 12. The printing unit ofclaim 11 wherein said v-printing unit is fixed.
 13. The printing unit ofclaim 10 wherein said first printing group and said second printinggroup can be coupled together.
 14. The printing unit of claim 13 whereinsaid first and second printing groups are adapted to print at least oneweb.
 15. The printing unit of claim 10 wherein said first, second,third, and fourth transfer cylinders are engageable with one of saidfirst and second counter-pressure cylinders.